Coleoptera: Geotrupidae: Bolboceratinae) Discussion J
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©Wiener Coleopterologenverein (WCV), download unter www.biologiezentrum.at 236 Koleopt. Rdsch. 81 (2011) Koleopterologische Rundschau 81 237–242 Wien, September 2011 retentions, and in hygropetric habitats. Absent from larger water bodies. The fact that the ventral eye-portion is very small suggests that the species avoids fully submerged habitats. DISTRIBUTION: Taiwan. A new Kenyan species of Bolboceras KIRBY (Coleoptera: Geotrupidae: Bolboceratinae) Discussion J. KRIKKEN Specimens of A. jengi and A. smetanai were compared to hundreds of specimens of Anacaena spp. from China and other Southeast Asian countries. This clearly showed that the two species described herein are endemic to Taiwan. Island endemism of Anacaena is not uncommon. Other species are restricted to Madagascar (KOMAREK 2004), New Guinea (KOMAREK 2009) and New Abstract Caledonia (KOMAREK 2010), respectively. Both new species are very similar to species from Four species of Bolboceras KIRBY, 1819 (Coleoptera: Geotrupidae: Bolboceratinae) have been China. Whether they form a clade is unclear at present. Potential morphological synapomorphies recorded from sub-Saharan Africa. In this paper, a new species, B. kenyense, is described from Kenya. are not apparent. An unusual ecological feature shared by both is that they occur in a broad The genus is briefly characterized and a key to the Afrotropical species of Bolboceras is given. variety of different wet habitats. Anacaena smetanai seems to avoid fully submerged habitats. Both species were collected from rotting plant material, in very small stagnant water bodies, and Key words: Coleoptera, Scarabaeoidea, Geotrupidae, Bolboceratinae, Bolboceras, key, new species, in hygropetric localities, specimens of A. jengi also in small creeks. This is surprising as all Kenya. hitherto described species of Anacaena are either strictly aquatic (most species) or only found in terrestrial habitats (some species from Madagascar and New Caledonia). Introduction Acknowledgements Most of the species in the genus Bolboceras KIRBY, 1819 occur in South Asia (particularly the Indian Subcontinent, cf. KRIKKEN 2011). Four species have been reported from sub-Saharan I am grateful to the water beetle team of the NMW, particularly to M.A. Jäch and H. Schönmann Africa. A new species from Kenya is added herein. This species is represented by three major for their friendly support and the opportunity to use the facilities of the Coleoptera collection. and two minor males, which, judged from their genitalia, belong to a single species – they are My thanks also go to R.G. Beutel (Jena, Germany) for critically reading the manuscript, and to from Tsavo and Meru. The predominant natural vegetation in these regions, as in most of central A. Smetana and M.-L. Jeng for valuable comments on the bionomics of the species. I am also and southern Kenya, is deciduous orthophyll savanna. Virtually all East African Bolboceratinae grateful to A.N. Newton (FMNH) and M. Fikáček (NMP) for the loan of the material. in the collections at hand (members of other genera included) were collected at light. Bolboceras specimens were not commonly seen during visits to East Africa – my campaigns, including an Zusammenfassung estimated total of 400 hours collecting at light during rainy seasons, spread over almost a decade, yielded only nine specimens (four of these are females close to another species, B. niloticum Zwei endemische Arten der Gattung Anacena von Taiwan werden erstmals beschrieben und BOUCOMONT, 1928). Representatives of certain other genera of Bolboceratinae appeared more durch differentialdiagnostisch relevante, morphologische Details illustriert. Beide Arten sind numerous. endemisch für Taiwan, aber morphologisch Arten vom chinesischen Festland sehr ähnlich. The shape of the head and pronotum (their outline and pattern of protrusions and impressions), Ungewöhnlich ist, dass beide sowohl in sehr unterschiedlichen aquatischen, als auch feuchten along with the structure of the male genitalia, are the basic features of the genus, their details terrestrischen Habitaten vorkommen. varying according to species. For more generic background on Bolboceras and technical conventions see my review of the group of Oriental species around B. nigricans WESTWOOD, References 1848 (KRIKKEN 2011). In this paper the genus is diagnosed and explicitly contrasted with other Afrotropical Bolboceratinae (currently ca. 110 species in ca. 15 genera); a key to the five known KOMAREK, A. 2004: Taxonomic revision of Anacaena. I. Afrotropical species. – Koleopterologische Afrotropical species is given, and the new Kenyan species is described and illustrated. I am sure Rundschau 74: 303–350. that more African Bolboceras species will be added in the years ahead, thus warranting a full KOMAREK, A. 2009: Taxonomic revision of Anacaena Thomson, 1859, V. New Guinea (Coleoptera: synopsis and a phylogenetic analysis. Work on Asian Bolboceras and other Bolboceratinae is in Hydrophilidae). − Koleopterologische Rundschau 79: 197–254. progress. KOMAREK, A. 2010: Taxonomic revision of Anacaena Thomson, 1859, VII. Indonesia except Papua (Coleoptera: Hydrophilidae). − Koleopterologische Rundschau 80: 113−128. In passing it may be noted that, although recent papers have expanded and improved our knowledge on bolboceratine diversity and distribution in Africa, nothing particular has appeared Dr. Albrecht KOMAREK on Bolboceras as currently conceived. The short generic account in KRIKKEN (1984, under Johann Straußgasse 39, A – 2340 Mödling, Austria ([email protected]) Indobolbus) aside, the present paper must be the first with substance since PAULIAN (1941). 44983P_Coleopterologen_81_Kern_V3.indd 247 17.10.11 09:56 ©Wiener Coleopterologenverein (WCV), download unter www.biologiezentrum.at 238 Koleopt. Rdsch. 81 (2011) KRIKKEN: A new Kenyan species of Bolboceras (GEOTRUPIDAE) 239 Bolboceras KIRBY, 1819 DIAGNOSIS: Frons with long, transverse, interocular ridge (length at least half of interocular distance); remainder of head surface lacking non-marginal ridges or other protrusion(s), fine ridge issuing from genal angle (delimiting eye canthus) on each side. Clypeal outline subtrapeziform or tapering to anteromedian point (marginal border of clypeus never evenly arcuate-convex in full face view). Eye canthus not completely dividing eye into upper and lower part (i.e., canthus not reaching an expanded temporal lobe), distal section of canthus narrowing to rounded tip (with angle or tubercle on anterior edge, separating straight proximal from arcuate distal section). Pronotum with anterior declivity topped by transverse row of four variably pronounced protrusions. Anteromedian margin of pronotum without any protrusion(s). Pronotal base marginate (variably delimited in front of scutellum). Scutellum broad, lateral sinuate edges fitting against elytra without slit. Seven finely punctate striae between elytral suture and humeral umbone, stria 1 reaching sinuate scutellar side, others reaching elytral base (which is emarginate). Antennal club large but not conspicuously inflated; central disc on internal side of antennomere 1 glabrous, but not abruptly separated from surrounding pubescent surface. Abdominal tip unmodified. Mesocoxae distinctly separated by (anteriorly abruptly declivous) metaventral process. Protibia with six tapering denticles on outer edge; protarsal segment 1 not much longer than 2. Aedeagus with strongly sclerotized (dark-brown) mobile pair of stalks on median apparatus, usually (when at rest, in non-extruded state) accommodated inside relatively simple parameral sheaths. Sexual dimorphism (as far as known) negligible. Unicolourous yellow to brown. Dorsum generally glabrous. Body length 6–17 mm. Immature stages unknown. TYPE SPECIES: Scarabaeus quadridens FABRICIUS, 1781 (ICZN 2006; cf. KRIKKEN 2011). Junior synonym: Indobolbus NIKOLAJEV, 1979, same type species. RANGE AND ECOLOGY: Oriental (ca. 20 spp.), Palaearctic (1 sp.), Afrotropical (5 spp.). No records from central and southern parts of Africa. Open forest and savanna, at light; tunnellers, possibly associated with hypogeic fungi. Comments on previously described species (see key below) The African record of Bolboceras nigricans, common in parts of India, is based on a single worn male from Tanzania: Dar-es-Salaam (ex Boucomont coll., MNHN, KRIKKEN 2011); fresh material is needed to confirm the identity and/or exclude accidental introduction or mislabelling. The African records of the reputedly Afro-Oriental B. inaequale WESTWOOD, 1848, from as far west as Senegal, are based on PAULIAN (1941) and equally need further verification – preferably on fresh series including males. The description by PAULIAN (1941) contains some errors. For instance for B. niloticum he gave a body length (6–7 mm) different from the original description by BOUCOMONT (1928: length 8–11 mm). I studied a topotypical female of 11 mm, identified by Boucomont in 1930 (BMNH, forebody in Fig. 6). PAULIAN (1941) added records of B. gaujani FAIRMAIRE, 1892 from regions around Djibouti (the type came from Obock); neither he nor I could trace the type. His description of the pronotal ornamentation differs from that of FAIRMAIRE (1892). PAULIAN (1941: fig. 21) gives a drawing of the head of his B. gaujani. Figs. 1–6: Bolboceras, 1–5) B. kenyense, holotype (major male), pronotal width 8.0 mm; 6) B. niloticum, Key to Afrotropical Bolboceras species (major males) topotype (female, Sudan: Medani), pronotal width 8.1 mm. – Habitus, 1) dorsal, 2) lateral, 3) oblique.